Chocolate wrapping foil specifications for automatic lines: dead-fold, thickness, coating, and roll setup
Chocolate wrapping foil specifications for automatic lines: dead-fold, thickness, coating, and roll setup
Machine-ready chocolate wrapping foil specifications start with the product, wrapping style, and machine manual. They then fix the foil construction, accepted gauge, web or cut size, core and reel limits, unwind and food-contact sides, print repeat and eye mark, splice rule, and the evidence used during receiving and line trials. A request for “gold food-grade foil, 12 micron” leaves most of that work undone.
Written by Qixin Packaging for chocolate manufacturers, co-packers, converters, packaging engineers, distributors, and purchasing teams qualifying foil for an existing or new wrapping line.
Quick answer:
Do not approve chocolate foil from colour and micron alone. Record the wrap route, exact machine, material construction, accepted thickness, width or cut size, core and reel limits, unwind/contact sides, print registration, splice policy, and trial method. The machine manual controls the allowed range. The line trial confirms whether the finished construction works with the actual chocolate and tooling.
The minimum specification has more than a micron number
Useful chocolate wrapping foil specifications let a converter reproduce the material and let a receiving team decide whether a delivered roll matches the approved version. If either team still has to guess the contact side, core, print pitch, or splice rule, the description is not finished.
Eight blocks that make the purchase line reproducible
| Specification block | Fields to write | What the fields control |
|---|---|---|
| Product and wrap | Chocolate shape, dimensions and range; wrapping style; fold or closure sequence; one or two materials. | Cut length, fold path, tooling contact, coverage, closure. |
| Machine | Make, model, format set, approved material family, speed used for the trial. | Allowed material and reel envelope, feed and cut behavior. |
| Foil construction | Unsupported foil, embossed foil, lacquered foil, foil-paper laminate, or another defined laminate; alloy and temper when controlled. | Dead-fold, strength, surface friction, cut, print, barrier, closure. |
| Dimensions | Base foil gauge, total construction caliper where relevant, web width or cut-sheet size, tolerances and test methods. | Tool fit, fold volume, knife load, roll mass, quote comparison. |
| Roll setup | Core ID, maximum reel OD and weight, roll face, unwind direction, inside/outside winding, edge and telescoping rule. | Shaft fit, guarding clearance, web path, roll change, tracking. |
| Print and surface | Artwork revision, colour standard, print repeat, eye-mark size and position, print side, food-contact side, emboss pattern and orientation. | Image position, sensor reading, scuff, set-off, consumer-facing finish. |
| Conversion and compliance | Primer, ink, lacquer, adhesive or seal coating; intended use; supporting declarations and restrictions. | Finished food-contact route, migration review, sealing or gluing. |
| Splice and acceptance | Permitted splice count and construction, marking, rejected length, sampling, trial quantity, defect definitions and disposition. | Automatic detection, product rejects, downtime, complaint evidence. |
The line does not read a sales description. It responds to a physical construction, a web path, a product, and a set of controls. That is why two foils with the same nominal gauge can run differently, and why a roll that works on one model cannot be approved for another from the label alone.
Build chocolate wrapping foil specifications from the wrapping route
A rectangular tablet, a round praline, a hollow figure, and a double-twist piece do not ask the material to do the same job. The wrapping style determines where the foil is pulled, cut, folded, twisted, smoothed, or sealed.
| Wrapping route | Typical product | Material work | Fields to settle first |
|---|---|---|---|
| Envelope or letter fold | Bars, tablets, enrobed pieces, wafers. | Clean cut, controlled feed, repeatable fold position, fold retention. | Product tolerance, cut length, web width, dead-fold, band or paper route. |
| Bunch or figure wrap | Balls, eggs, hearts, coins, hollow figures. | Conformation around curves, local folds, smoothing, image orientation. | Product geometry, foil size, formability, surface, print position, tooling contact. |
| Double twist | Small bars, pieces, sweets and wrapped chocolate portions. | Repeated torsion at two ends without early tear or untwist. | Construction, twist area, cut size, product ends, closure retention. |
| Foil plus band or paper | Bars needing an inner foil and a printed outer component. | Two feeds must arrive in the correct position and remain compatible through the fold. | Two-material sequence, glue if used, registration, relative widths, splice handling. |
| Actively sealed construction | Products or materials whose closure depends on heat, cold seal, or adhesive. | Seal or bond performance becomes part of the package function. | Seal side, coating, seal window, jaw contact, contamination risk, validation method. |
Cormac’s RG machine, for example, lists bunch wrap, front folding, double twist, heat sealing, and figure foiling on one equipment family. That variety is evidence for the decision order. “Chocolate foil” is an application name. The wrapping route describes the work the material must survive.
Dead-fold means fold retention, not general softness
Dead-fold is aluminum foil’s ability to retain a fold after the forming force is removed. On a chocolate bar, that helps the wrapper stay close at the overlap and ends. On a shaped piece, it helps many small folds remain around the contour. EAFA identifies dead-fold as a reason foil works for bars and chocolate novelties.
Soft hand feel is not a complete substitute for dead-fold. A construction may feel easy to bend yet recover after folding. A laminate may feel stronger because of its paper or film layer while its closure behaves differently from unsupported foil. Embossing changes the surface and local geometry, but it does not create one guaranteed feeding or fold result.
A comparative fold-retention record for incoming samples
When no contract method exists, a buyer can use an internal comparison to keep observations consistent. Cut control and candidate specimens in the same rolling direction and size. Condition them together. Fold each specimen around the same clean gauge block with the same tool and stroke. Photograph the fold immediately and after a fixed internal interval. Record opening, cracking, coating disturbance, and whether the fold changes after handling.
This is a comparative shop-floor record, not a standardized dead-fold test. It can show that two samples behave differently under one controlled setup. It cannot set an industry limit, predict every machine fold, or replace a production trial.
Thickness, alloy, temper, and construction belong in chocolate wrapping foil specifications
Gauge affects the amount of aluminum in the fold and the roll, but it is not the only variable behind stiffness, elongation, tear behavior, or fold retention. EAFA states that shape, thickness, alloy, and temper are selected to create the needed performance. ASTM B479 also covers several alloy families for annealed packaging foil rather than declaring one universal chocolate alloy.
Going thicker may make a sheet feel more substantial and can change how it reaches a fold. It also adds roll mass, changes the material volume passing the knife and fold tooling, and increases aluminum use. If a tear begins at a damaged slit edge or blunt knife, extra gauge may hide the symptom without correcting the source. If a fold opens because the construction or closure route is wrong, extra gauge can add cost while leaving the failure in place.
Decision rule: use the exact machine’s accepted material and gauge range as the starting envelope. Compare candidate constructions inside that envelope on the real product. Approve the finished specification from trial evidence, not from a generic supplier range.
Unsupported, embossed, paper-backed, and coated foil are different products
| Construction | What changes | Approval questions |
|---|---|---|
| Unsupported foil | The aluminum carries the fold, surface, cut, and much of the handling behavior. | Gauge, alloy/temper if controlled, lacquer or print route, edge quality, rolling direction, contact side. |
| Embossed foil | Texture changes appearance, effective surface, local bending and how layers contact each other. | Pattern, depth, direction, total caliper, nesting or blocking, sensor and print effect. |
| Foil-paper laminate | Paper adds another strength, friction, print, moisture, cut, fold and glue component. | Layer weights, adhesive, paper direction, total caliper, delamination, contact side, two-material or single-web route. |
| Lacquered or printed foil | Surface slip, rub resistance, set-off, colour, heat response and food-contact review may change. | Coating identity, coat side, intended use, TDS, artwork, cure, migration assessment route, scuff test. |
| Sealable laminate or coating | Closure depends on a defined sealing system rather than fold retention alone. | Seal side, temperature/time/pressure window, jaw geometry, product heat exposure, seal test and storage route. |
LoeschPack’s LTM documents embossed and paper-backed aluminum foil and can process two materials in one station. EAFA also notes that foil-paper laminates can add strength and machinability while retaining dead-fold. Those points support multiple valid constructions. They do not establish a ranking without the product, machine, closure, and commercial target.
Print and coating approval starts with the food-contact side
“Food-safe ink” is too vague for a finished wrapper. The approval file needs the complete layer order, the side facing the chocolate, the print and lacquer sides, the intended food and storage conditions, and the supporting documents for that use.
The FDA treats packaging components such as colorants, coatings, and adhesives as food-contact substances when their use places them in that system. EU Regulation 1935/2004 sets the finished-material objective: under normal or foreseeable use, constituents must not transfer at levels that endanger health, unacceptably change the food, or worsen its organoleptic characteristics.
EuPIA’s guidance adds practical converter questions. Migration can occur from direct contact, set-off in the roll or stack, or gas-phase transfer. A technical data sheet should state whether the ink is intended for a non-food-contact surface or intentional direct contact and list relevant restrictions. The converter and final packer still have work to do on the finished structure.
Keep these items in the print approval file
- signed layer diagram showing aluminum, primer, ink, lacquer, adhesive, paper or film;
- identified chocolate-contact side and consumer-facing side;
- ink, coating and adhesive TDS plus relevant statements of composition or compliance information;
- intended food type, storage time, temperature route and any direct-contact claim;
- artwork revision, colour target, print repeat, eye-mark drawing and unwind diagram;
- rub, set-off and migration assessment route for the finished construction.
For print-process and artwork preparation outside the machine-specific fields, use Qixin’s separate aluminum foil printing solutions article.
Machine data proves why one universal foil specification fails
Published OEM data belongs in chocolate wrapping foil specifications only when it is kept beside the model name. It shows the type of field a buyer should request. It does not let a supplier transfer one model’s limits to another line.
| Published machine example | Material and reel information | Controls or options that affect the specification | Proper use of the example |
|---|---|---|---|
| Theegarten-Pactec CFW-S | Aluminum foil and laminates; reel up to 350 mm; core 70 to 76.2 mm. | Automatic splicer, print-mark registration, splice detection, web tracking, second material feed, heat-seal option. | Shows that core, reel, registration and splice fields belong in the specification. |
| Zum Wald cb12 | Aluminum foil 0.010 to 0.020 mm; width up to 250 mm; bobbin up to 220 mm and 10 kg; sleeve about 70 to 80 mm. | Built for chocolate bars with its own product and format envelope. | A model-specific example. It is not the standard range for all chocolate foil. |
| LoeschPack LTM | Embossed or paper-backed aluminum foil among several inner-wrap materials. | Two packaging materials in one station; varied folding and closing; optional automatic splice device. | Shows that construction and two-material handling can be machine functions. |
| Cormac RG | Width 80 to 300 mm; cut length 60 to 250 mm; reel up to 250 mm; core 45 to 78 mm. | Several wrapping styles, print control, no-product-no-wrap, second unwind and splice options. | Shows how product style, cut size, print and second-web fields change together. |
The examples differ. That difference is the point. Send the current machine manual page or a written OEM confirmation with the RFQ. For a rebuilt line, also record the installed core chuck, reel guard clearance, sensor, knife, splicer, and any non-standard retrofit. The model plate alone may not describe the current machine.
Registration and splice data complete printed chocolate wrapping foil specifications
A printed wrapper can be dimensionally correct and still place the logo across a fold. The artwork drawing needs a product datum, print repeat, cut position, eye-mark size and position, sensor side, print side, contact side, and unwind direction. Use a small physical mock-up to mark the consumer-facing panel and fold sequence before approving the cylinder or plate layout.
Theegarten-Pactec’s CFW-S uses photoelectric print-mark registration to position the image and can detect manufacturer splices and eject affected products. That tells the buyer to define how a splice is made, where it is marked, whether it is detected, how much web or how many products are rejected, and whether a roll with a splice is acceptable.
Do not hide the splice rule in general terms. Write the allowed count, tape or joining construction, marker position, minimum distance from roll end if required, and the disposition of the detected section. A perfectly visible splice can still create unexpected waste if the quotation did not assign that waste.
Use line symptoms to choose evidence, not to assign blame
One symptom can come from several systems. Preserve the roll, machine settings, rejected wrapper, and product before changing multiple variables. A trial that changes tension, knife, temperature, product, and foil at once may restore production but destroy the root-cause evidence.
A symptom-to-evidence worksheet for the first controlled check
| Line symptom | Preserve first | Material questions | Machine or product questions | Next controlled check |
|---|---|---|---|---|
| Fold opens | Finished fold, time after wrap, lot and product size. | Construction, temper, gauge, laminate direction, coating. | Fold sequence, tooling stroke, overlap, product tolerance, need for seal or glue. | Run control and candidate with the same product and settings; compare fold retention. |
| Tear at knife | Cut edge, direction, knife position and frequency. | Slit-edge damage, gauge, laminate or emboss variation. | Knife sharpness, clearance, contamination, web tension, cut timing. | Inspect edge under magnification and cut control web after the same knife check. |
| Tear at fold or corner | Tear origin, rolling direction, product corner and fold tool mark. | Formability, local defect, coating crack, laminate bond. | Sharp product edge, tight radius, fold stroke, misfeed, product temperature. | Rotate specimen direction or use matched products without changing other settings. |
| Wrinkles or poor smoothing | Wrapper map showing where wrinkles begin. | Caliper, emboss, curl, flatness, friction, laminate direction. | Product shape range, guide alignment, smoothing tool, tension, timing. | Sort products by geometry and compare wrinkle location at fixed settings. |
| Web walks sideways | Roll edges, core position, tracking trend and unwind side. | Telescoping, edge alignment, cross-web caliper, curl. | Core/chuck fit, guide and roller alignment, brake, web path, tracking control. | Measure roll/core geometry before adjusting the guide; run a known control roll. |
Registration, feeding, splice, and surface symptoms
| Line symptom | Preserve first | Material questions | Machine or product questions | Next controlled check |
|---|---|---|---|---|
| Print drifts | Successive wrappers, eye mark, repeat readings and sensor status. | Print repeat variation, mark contrast, splice, stretch of laminate layer. | Sensor position, feed roller slip, web tension, cut timing, dirty optics. | Measure repeat off-line and check the sensor with the approved mark sample. |
| Double feed or jam | Jam location, layers involved, roll condition and machine stop log. | Blocking, static, emboss nesting, coating slip, cut consistency. | Air support, separation, feed roller, guide, humidity, product timing. | Separate static/blocking observations from feed timing and air settings. |
| Splice reject or break | Splice sample, marker, detection signal and rejected product count. | Tape, overlap, thickness step, marker location, splice strength. | Sensor setup, tension transient, splice path, automatic change sequence. | Run an approved dummy splice under controlled conditions and record the rejected length. |
| Scuff or colour transfer | Unwound surfaces, contact faces, time and pressure in roll or stack. | Ink/lacquer cure, rub resistance, set-off, emboss peaks, slip. | Guide contact, pressure, heat, storage, rewind tension, dirty surfaces. | Compare protected and contact areas using the agreed rub and storage route. |
The table is a differential diagnosis. It tells the team what to preserve and what to change one variable at a time. It does not convert a symptom into a supplier rejection.
Receiving and line trial: keep the first condition intact
- Freeze the approved revision. Record purchase order, specification, artwork, machine, format set, product size range, lot, roll and carton identity.
- Inspect the roll before adjustment. Photograph both faces, edges, core, labels, wrapping, telescoping, damage and splice markings before mounting.
- Verify construction and orientation. Confirm web width, core ID, reel OD and weight, unwind direction, print side, contact side, eye mark, repeat and layer order.
- Retain start, middle and end samples. Keep labelled specimens across the roll and record the position of every manufacturer splice encountered.
- Run the approved startup window. Use the documented machine setup and actual product. Record speed, stops, rejects, adjustments and time rather than writing only “runs well”.
- Change one variable at a time. When a fault appears, preserve the failed sample and compare a controlled change in material, machine setting, tool or product geometry.
- Apply the agreed decision rule. Use the contract’s sample plan, defect definitions and acceptance limits. Archive the evidence that links the decision to the roll and specification revision.
Copyable receiving and trial record
| Record block | Fields to retain |
|---|---|
| Identity | Supplier, PO, specification and artwork revision, lot, roll, carton, date, operator. |
| Product and machine | Chocolate type, shape, dimensions, temperature if controlled, machine make/model, format parts, wrap route. |
| Material | Layer construction, gauge/caliper, width, core, reel OD/weight, unwind, print/contact side, emboss, colour. |
| Print and splice | Artwork, repeat readings, eye mark, image position, splice count/location, detector response, rejected length. |
| Settings and output | Speed, tension or brake setting as displayed, registration setting, seal/glue setting if used, run time, good count, reject count, stops. |
| Fault evidence | Time and roll position, failed wrapper, photo, machine event, product geometry, one-variable change and result. |
| Decision | Accepted range, restrictions, rework or rejection, approvers, retained samples and next revision. |
Copy this structure into the chocolate foil RFQ
The fields below turn chocolate wrapping foil specifications into a manufacturing brief that a converter can quote and a line team can later verify.
Product: chocolate type, shape, dimensions and allowed variation
Wrapping route: envelope/fold, bunch/figure, double twist, foil plus paper/band, or sealed construction
Machine: make, model, serial or retrofit notes, approved manual page, format set and intended trial speed
Construction: unsupported, embossed, lacquered, printed, foil-paper or other defined laminate; layer order; base foil alloy/temper if controlled
Dimensions: base foil gauge, total caliper if relevant, web width or cut size, tolerances and measurement methods
Roll: core ID, maximum reel OD and weight, face width, winding side, unwind direction, edge/telescoping expectation
Print: artwork revision, colour reference, repeat, cut position, eye mark, sensor side, consumer face and food-contact face
Coating and food contact: primer, ink, lacquer, adhesive or seal coating; intended use; TDS and compliance information required
Splices: allowed count, joining method, marker position, detector route and rejected-web responsibility
Approval: sample quantity, startup window, retained samples, defect definitions, acceptance limits, sign-off and change-control rule
If roll mass, length, core tare, and reel OD also need reconciliation, use the separate aluminum foil roll weight and length method. Keep those quantity checks separate from machine runnability.
What chocolate wrapping foil specifications cannot decide without your line
No web article can select the final gauge, tension, line speed, core, reel size, eye mark, splice rule, or acceptance tolerance for an unknown machine. It also cannot approve a direct-food-contact print or coating without the intended use and finished-construction documents.
The missing evidence is practical: the current machine manual, installed hardware, product geometry and temperature, wrapping sequence, artwork, layer structure, intended market, and defined trial result. A supplier can use those records to prepare a relevant construction. The buyer and packer still control approval on the actual line.
Questions about chocolate wrapping foil specifications
What thickness should chocolate wrapping foil be?
Use the range accepted by the exact wrapping machine and construction, then qualify it with the real chocolate and tooling. One Zum Wald cb12 example publishes 0.010 to 0.020 mm, but that range belongs to that model. It is not a universal chocolate foil specification.
What is dead-fold in chocolate foil?
Dead-fold is the ability of foil to retain a fold after the forming force is removed. It helps a wrapper stay close to bars and shaped pieces. It should be compared on a defined specimen and confirmed through the actual machine fold.
Is embossed chocolate foil easier to run than smooth foil?
Not automatically. Embossing changes texture, effective caliper, layer contact, appearance and local bending. Depending on the pattern and machine, it can also affect blocking, sensor response, feeding or print. Compare the defined embossed construction with the smooth control on the same line.
Can printed foil touch chocolate directly?
Only when the finished construction and intended use support that contact. Identify the food-contact side, ink, lacquer, primer and other layers, then review the relevant technical and compliance information. A general “food-safe ink” statement is not enough.
Why does the print move away from the center during wrapping?
Possible causes include print-repeat variation, eye-mark contrast, sensor position, feed-roller slip, web tension, cut timing, a splice or product-position variation. Retain successive wrappers and repeat readings before changing several settings.
What information should be sent to a chocolate foil supplier?
Send the chocolate shape and size range, wrap route, machine make/model and manual limits, foil construction, gauge, width or cut size, core and reel limits, unwind/contact sides, print repeat and eye mark, splice rule, intended food-contact route, and trial acceptance method.
Technical sources and use limits
- European Aluminium Foil Association, Confectionery: dead-fold, unsupported foil, foil-paper laminates, coatings, embossing, slitting and edge quality.
- European Aluminium Foil Association, Properties: dead-fold and the linked role of shape, thickness, alloy and temper.
- ASTM B479-19 public scope: annealed aluminum and aluminum-alloy foil for flexible barrier and food-contact applications.
- Theegarten-Pactec CFW-S data sheet: model-specific materials, reel/core dimensions, print registration, web tracking and splices.
- Zum Wald cb12: model-specific foil gauge, width, bobbin and sleeve data.
- LoeschPack LTM: embossed and paper-backed aluminum foil plus two-material handling.
- Cormac RG: wrapping styles, print control, second unwind, splice options and model-specific material dimensions.
- Theegarten-Pactec suction-supported sealing: an OEM example showing why active closure and material construction must be specified together.
- US FDA food packaging and food-contact substances: intended-use and migration basis for packaging components.
- US FDA food types and conditions of use: why the intended food and temperature or storage route belong in the approval file.
- EU Regulation 1935/2004: general requirements for finished food-contact materials.
- EuPIA printing-ink guideline: print-side, migration, set-off, TDS and information-sharing context.
All machine figures above are attributed examples. The current machine manual, installed configuration, buyer-supplier specification, intended food-contact use, and production-line trial control the final decision.
Preparing a chocolate foil RFQ?
Send the machine make and model, manual limits, chocolate dimensions, wrapping style, construction, artwork repeat, unwind diagram, contact side, splice rule, and trial method. Review the current QXCL chocolate foil route or send the completed specification to Qixin for a construction review.
